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期 刊 ：植物保护学报 2009年

关键词：虫螨腈；甜菜夜蛾；增效剂；保护酶；解毒酶；

Keywords:chlorfenapyr, beet armyworm, synergism, protective enzymes, detoxifying enzymes,

摘 要 ：为探明虫螨腈对甜菜夜蛾幼虫体内生化代谢的影响及酶抑制剂对虫螨腈的增效潜力,采用点滴法测定了虫螨腈对甜菜夜蛾3、4、5龄幼虫的毒力和顺丁烯二酸二乙酯(DEM)、增效醚(PBO)、磷酸三苯酯(TPP)对虫螨腈的增效作用,并采用生化分析法测定了LD₂₅和LD₅₀剂量虫螨腈对甜菜夜蛾体内保护酶系和解毒酶系的影响。结果表明,虫螨腈对甜菜夜蛾不同龄期幼虫的毒力差异不大,处理后24h和48h的LD₅₀基本相同。PBO对虫螨腈有拮抗作用,增效比为0.21,而DEM和TPP对虫螨腈无增效作用。虫螨腈对甜菜夜蛾幼虫体内超氧化物歧化酶具有激活作用,对过氧化氢酶、过氧化物歧化酶及羧酸酯酶具有先抑制后诱导的作用;虫螨腈处理后6~24h,谷胱甘肽-S-转移酶活性显著提高,最高为对照的1.85倍;处理6h后,甜菜夜蛾体内细胞色素P450含量明显下降,而12~24h后,又明显上升,最高时为对照的1.86倍。

Abstract:In order to identify the effect of chlorfenapyr on biochemical metabolism of beet armyworm, Spodoptera exigua (Hübner), and evaluate the synergism of enzyme inhibitor, the toxicity of chlorfenapyr to beet armyworm larvae and the synergism of triphenyl phosphate (TPP), piperoayl butoxide (PBO) and diethylmaleate (DEM) to chlorfenapyr were detected by using topical application method. The influence of chlorfenapyr on the detoxifying and endogenous protective enzymes in beet armyworm larvae was determined with biochemical measurement at the dose of LD₂₅and LD₅₀. The results indicated that beet armyworm was still sensitive to chlorfenapyr with the semblable toxicity to different instars larvae of S.exigua and the LD₅₀ to beet armyworm 24h and 48h after treated by topical application was also the nearly same. The toxicity of chlorfenapyr could be antagonized by PBO with the synergism ratio of 0.21, but not by TPP or DEM. Superoxide dismutase activity was induced by chlorfenapyr, while activities of catalase, peroxidase, and carboxylesterase were inhibited first and then induced after treated with chlorfenapyr. GST activity was induced significantly by chlorfenapyr 6-24h after treated by chlorfenapyr and was 1.85-fold of the control 24h after treatment. The content of cytochrome P450 was inhibited 6 h after treated with chlorfenapyr, but induced 12-24h and was 1.86-fold of the control 24h after treatment.

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